Electrical measuring instrument.



'W. KLINGKERT. v V ELECTRICAL MEASURING INSTRUMENT.

APPL IOL'I 'IDI rnnn A2B.8,190B.

I 1,008,549, Pafien zed Nov. 14, 1911.

WITNESSES: [N RENTER.

m k\ .gw. 7102mm IfLINCKEHYT ATTY.

- .wnnmgn nmex m,

or BERLIN. dentistr assxenonlro assent; amicmdedu- PANY, a coarozaa'rron ornnw'ronx. v

nnnc'rmcan MEASURING INSTRUMENT.'

Specification of Letters Patent. Application filed April a, 1908. Serial No. 425,519.

Patented 50v. 14,.191'1.

ermai ently secured to on of the members i To whom it im'y concem:

Be itknown that I, )VILHELM KLINCKERT, y

1 Measuring 1 a subjectof the King of Prussia, residing at have invented certain new Berlin, Germany, and useful Improvements in an Electrical Instrument, of which the fol-v lowing-is aspecification. y My nventionrelates to electrical measuring instruments, 1 1.

and more particularly to truments of the DiArsonval and similar types, in which a current carrying coil moves hro exi'sts 'ln-a narrow air gap n the intense magnetic field which the magnetic circuit of a powerful permanent magnet. The instruments ofthis type most commonly 415;!1} consist. of two curved pole ple'ces mo lmted-face'to face, with a cylindrical core liked betweenthe mto have a narrow arcshaped air gap betweenthe core and each pole co r arc-shaped airgaps, mounted to rotate about the axisiof the core in f-cur ent;

y 26 gaps fbetween.the pole pieces and theccre 1 .arelequal .to each t piece, and a'rectangular current carrying coi1,=;with,its sides extending through the response to variations I V H Since the accuracy and value of .the instrument are greater when the an er and areof uniform.

,.wid th,,the eoremust be adjusted and set ell c nc n ri 80.

and inerea'se thecostof w. ilegreat' idifiiculty is encountered 111.

v with the i emt bn vl chr q i I the instrument,

iiaifahe e n m d objhctlo'f, my invention is to provide an electrical; measuring instrument. capable fbein'gjeasilydismounted and reassembled ithoutgafielctingits accuracy, andha-ving a magnetic system so constructed that theva 40 rious parts'QWhich are'made veryaccurately i and, rapidly by-means of diesor templets,wi1l

' fit'ltog'ether. V

he was m "1"" ry'ing moves,; v A g other in 'exactend definite relation by means Iation to each e her, therhby' instrunrent with a ma" 'etic r yiflhd xa lt withofit .1 us l n f r 1 9 51 fi t n iyin'g cutimy' v i ieii v "m mb rsvh H m t era i gap ie *Mefit iev E S as Piefmbly s e/a ole pieces by' a skllled workman roperly re-assembling the. instrument after andjinterlock when they are in was h eni I are 'nterlocked 'with" each'jl i casting or some similar process and is provided with grooves or r ,bs whiohfit into corresponding ribs or de: xressions' on; the other member. Inthe pri ferred form two semi-circular or curved pol e pieces mounted face to face are made subs 2antiallyintegral and are held infixed relat Lento each other by means of'brass space bl )cksmounted be. tween and rigidly secured'to-the op os ng ends of the pole ieces. lhe'space locks have grooves out in them to interlock with corresponding rojections on the core and since the inter ocliring gr-(oves and tions are made very .acci rately, eit er by casting or by means of dies'and templets,

the twofmembers must necessarily assume the exact position required with relation to each otherwhen the ribs a lid groovesonthe two members arecomplet :ly home and are interlocked.- a v i y My invention. will bestbe understood in connection with the accom panying drawin which shows one-of the ma 1y formsin whic it may be embodied, and i 1 which,

Figure 1 is a perspective view of the core invention; Fig. 2 a persp active view of the pole ieces of the inst-run ent; Fig. 3; a perspective view of the ole pieces and corein their assembled position; and'Fig. a lan viewbf'the entire magn :tic system '0 the instrument.

of a DArsonval instrume nt embodying my The moving coil and po inter of the instrument are not shown in ihe drawing, since these parts are of standar 1 construction and are mounted to rotate ab ut the axis.v of the cylindrical core. The in tgnetic field is. obtained by means-of the p nwerful permanent magnet 1 with its pole; connected to the ooved pole pieces: 2, .v 'hich' aremounted between them. 1 he op] osing finds} e' spas o ks Me 4, m j

. n m nt i 'el L1 d P spi block wil mm 'structed 'i'n anysui't'able my; a enable ie ee wit t was ace to face,,so as to lea re a circular S ace,

Agatha exact position v block 3 is provided a with .a longitudinal groove parallel to' theaxis of the circular pole ieces 2, while the. space block 4 is proangles to the axis. of the 'pole'pieces. The

..cylindricalcore,7 must 'bejmouhted'between h the combination with polepieces, of masses of non-magnetic material .rlgidly secured to.

the polepieces2 and exactly concentric with them, and this result is easily obtained by rovidi'ngithe core with interlocking proections which fit the grooves 5 and 6 and thereby position I the core exactly concentric? with" the polejpieces and also in proper lontudinal;' ,relation to them: In --thepreerred construction,- as shown in Fig. 1, the

' cylindrical iron core 7 is provided with a projection or guide bracket 8 ofbrass which exactly fits the. groove 5, while a second pro- 'jec-tion. or guide bracket-9, diametrically op- I posite-the first, makes a snug b 0 side's .of the grooves .5 and 6- fit closely the fit with the inner surface of the space ck to prevent movement of the core" toward either space block, and since at the same tim'e'the sides ofthe projections 8 and 9 the core is firmly -'posit1oned exactly concentric with "the pole pieces 2 merely -b sliding] the pro- 'fjections in the 'coreiinto te grooves on the space blocks. 'The 'pro'jec-tion or guide a bracket 9 is, a-lso provided' with a shoulder 10, whichfits snugly into the groove ,6, and

tions the 'core longitudinally between the means of dies and templets, and fit into and interlock with each-"other very accurately, the core ism'ounted exactly concentric with-thepolepieces and in 'proper po- {the parts are held-against displacement by bracket 9Hat each end-with lugs leiproject- 12 Iin'the space block 4 and sit-ion-axiall-yby merely sliding the guide brackets "-8 and!) into the grooves 5 and 6 nntil'the shoulder 10engages the bottom of the groove 6. After the core is in position means of af-stud 11 passing through va hole the guide bracket 9.

. The moving coil 's mounted exactly concentric with the core'and in-such a" position that it will swing about the core with a uni-' form f clearance. by' providing the guide ing heyon' '1 the-axis of the core'and sepa-.

:rated by a space greaterthan the length of 1 onitheenaotlzixis-ofthe core, and the bearthe core. Holes; are bored throngh the lugs ings forv the moving coil-"aremou'ntedfin Yule e r q whe the coil SD 'in'place,' I a e erred arrangement is that sct$iof my-invent-ion. vide near one end wima groovefi atnght I by'Letters Patent of the Un1ted'States,-1s','

into a hole 13 in these: holes, so that no. fitting or" adjusting rection transverse its axiswhereby said-core My invent on-maybe in many is held concentric with-said polepieces.

other forms than that shown and described and the terms of the appended claims are not restricted to the precise structure disclosed, but are intended to cover all changes and modifications within the .spirit and at I claimas new, and desire to secure 1.1111. an electric measuring: instrument,

said polepieces and provided with grooves one at right angles and the otherp'a'ra'llel to'jthe axis ofthe polepieces, and a. block of iron provided with projections, one of which engages one'of said. groove'stand the other of-whi'ch engages. both'sides and'the bottom of the other of said grooves to interlock the block of iron. with said'non-mag- I netic material against axial'movement 'one' direction and against both rotationand .2. In an electric measuringflinstrument, the combinationwith polepiec'es' zmoui'ited.v

face to face and a' magnetic coremountedf I between said polepi'ec-es, of non-magnetic space blocks between and rigidly secured to opposingends of said polepieces, and a. nonmagnetic coresupport interlocked with said I 's'paceblocks to hold the coreagainst axial by engaging the bottomof'the groove posi-' i movement in one direction-and against Both rotation and transverse movement in any:

a 3. an electric measuring instrumenfi tween said polepieces ,anda'moving: coil, of

non-magnetic space blocks between opposing ends of said polepieces,. said space hldcks having grooves between said'endsone.

at'ri'gh't' angles and the other "parallel to the "axisof said pole pieces,.and non-magnetic supportsfor said core; one. ofsaid supports having lugs adjacent eachend of-the core} to carry bearings for the moving coil and provided with a projection which fits into said groove and engages, both the'bottom and sides thereof .to interlock the. core with.

the polepieces against axial movement ,in

one direction and against-both rotation and transverse movement 1n any d1 rect1on.

4. In an electric measur ng instrument,

the combination with curved pole pieces mounted face to face -of space'blocks' of I non-magnetic material integrally secured to theopposingendsof said pole'piece's", a-cy- 26 Isaid core. interlockingsaid corew-ith the lindrical core, and means connectedwith since P1 gainstaxia1 move t one .dlrection and against Inoveme tiii any-(1L 5. In an electric -measu ring instrument, said core in only one direcw ion along itsgxis the combination with polepieces mounted and to hold the core in p(siti,on. 1o face to face', 015 non-magnetic space blocks In witness whereof I have hereunto' "set between said polepieces, a. magnetic core my hand this23rdda' of March-1908,

KLINCKEBT 5 mounted between said olepieeefs, and a flat non-magnetic support or said core thinner Witn: U than sald space blocks and interlocked with JULIUS Rlnnnnggsaid space blocks, to permit movement of 

